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High and high high alarms

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Indy

Industrial
Joined
Dec 14, 2012
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172
Location
GB
If a pressure transmitter is wired to a dcs (Analogue input) are the alarms generated by the dcs from this instrument when it passes its set points classed as Analogue outputs or are they still classed as Analogue inputs?

Thanks
 
Inputs.

An OUTPUT would be the DCS generating an OUTPUT.

The pressure transmitter is outputting a pressure signal that connects to a DCS INPUT. The DCS reads this INPUT, compares it to set points, and reacts accordingly.

Keith Cress
kcress -
 
It used to be easy.

A pressure transmitter gave you pressure signals as an analogue input into the DCS. What the DCS does with that data has nothing to do with the TX. Any output from the DCS could be in the form of a Digital ootput to some other device or system or maybe just creates a software command which shows up on the HMI as an alarm.

HH alarms tend to be generated from separate devices to the transmitter, especially if they are actually wired to the ESD panel.

These used to be switches, so a Digital input into the ESd or DCS.

But now more often, you find that it's actually a transmitter with a built in processor which outputs a digital signal DI into the panel.

An analogue output is a signal which varies between some valvues and is usually used to control something else (valve position e.g.)

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
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